1/*
2 * Copyright © 2018 Google, Inc.
3 *
4 * This is part of HarfBuzz, a text shaping library.
5 *
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
11 *
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 * DAMAGE.
17 *
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 *
24 * Google Author(s): Garret Rieger, Roderick Sheeter
25 */
26
27#ifndef HB_SUBSET_PLAN_HH
28#define HB_SUBSET_PLAN_HH
29
30#include "hb.hh"
31
32#include "hb-subset.h"
33#include "hb-subset-input.hh"
34
35#include "hb-map.hh"
36#include "hb-set.hh"
37
38struct hb_subset_plan_t
39{
40 hb_object_header_t header;
41
42 bool drop_hints : 1;
43 bool desubroutinize : 1;
44 bool retain_gids : 1;
45 bool name_legacy : 1;
46
47 // For each cp that we'd like to retain maps to the corresponding gid.
48 hb_set_t *unicodes;
49
50 // name_ids we would like to retain
51 hb_set_t *name_ids;
52
53 // name_languages we would like to retain
54 hb_set_t *name_languages;
55
56 //glyph ids requested to retain
57 hb_set_t *glyphs_requested;
58
59 // Tables which should be dropped.
60 hb_set_t *drop_tables;
61
62 // The glyph subset
63 hb_map_t *codepoint_to_glyph;
64
65 // Old -> New glyph id mapping
66 hb_map_t *glyph_map;
67 hb_map_t *reverse_glyph_map;
68
69 // Plan is only good for a specific source/dest so keep them with it
70 hb_face_t *source;
71 hb_face_t *dest;
72
73 unsigned int _num_output_glyphs;
74 hb_set_t *_glyphset;
75 hb_set_t *_glyphset_gsub;
76
77 //active lookups we'd like to retain
78 hb_map_t *gsub_lookups;
79 hb_map_t *gpos_lookups;
80
81 //active features we'd like to retain
82 hb_map_t *gsub_features;
83 hb_map_t *gpos_features;
84
85 //The set of layout item variation store delta set indices to be retained
86 hb_set_t *layout_variation_indices;
87 //Old -> New layout item variation store delta set index mapping
88 hb_map_t *layout_variation_idx_map;
89
90 public:
91
92 /*
93 * The set of input glyph ids which will be retained in the subset.
94 * Does NOT include ids kept due to retain_gids. You probably want to use
95 * glyph_map/reverse_glyph_map.
96 */
97 inline const hb_set_t *
98 glyphset () const
99 {
100 return _glyphset;
101 }
102
103 /*
104 * The set of input glyph ids which will be retained in the subset.
105 */
106 inline const hb_set_t *
107 glyphset_gsub () const
108 {
109 return _glyphset_gsub;
110 }
111
112 /*
113 * The total number of output glyphs in the final subset.
114 */
115 inline unsigned int
116 num_output_glyphs () const
117 {
118 return _num_output_glyphs;
119 }
120
121 /*
122 * Given an output gid , returns true if that glyph id is an empty
123 * glyph (ie. it's a gid that we are dropping all data for).
124 */
125 inline bool is_empty_glyph (hb_codepoint_t gid) const
126 {
127 return !_glyphset->has (gid);
128 }
129
130 inline bool new_gid_for_codepoint (hb_codepoint_t codepoint,
131 hb_codepoint_t *new_gid) const
132 {
133 hb_codepoint_t old_gid = codepoint_to_glyph->get (codepoint);
134 if (old_gid == HB_MAP_VALUE_INVALID)
135 return false;
136
137 return new_gid_for_old_gid (old_gid, new_gid);
138 }
139
140 inline bool new_gid_for_old_gid (hb_codepoint_t old_gid,
141 hb_codepoint_t *new_gid) const
142 {
143 hb_codepoint_t gid = glyph_map->get (old_gid);
144 if (gid == HB_MAP_VALUE_INVALID)
145 return false;
146
147 *new_gid = gid;
148 return true;
149 }
150
151 inline bool old_gid_for_new_gid (hb_codepoint_t new_gid,
152 hb_codepoint_t *old_gid) const
153 {
154 hb_codepoint_t gid = reverse_glyph_map->get (new_gid);
155 if (gid == HB_MAP_VALUE_INVALID)
156 return false;
157
158 *old_gid = gid;
159 return true;
160 }
161
162 inline bool
163 add_table (hb_tag_t tag,
164 hb_blob_t *contents)
165 {
166 hb_blob_t *source_blob = source->reference_table (tag);
167 DEBUG_MSG(SUBSET, nullptr, "add table %c%c%c%c, dest %d bytes, source %d bytes",
168 HB_UNTAG(tag),
169 hb_blob_get_length (contents),
170 hb_blob_get_length (source_blob));
171 hb_blob_destroy (source_blob);
172 return hb_face_builder_add_table (dest, tag, contents);
173 }
174};
175
176typedef struct hb_subset_plan_t hb_subset_plan_t;
177
178HB_INTERNAL hb_subset_plan_t *
179hb_subset_plan_create (hb_face_t *face,
180 hb_subset_input_t *input);
181
182HB_INTERNAL void
183hb_subset_plan_destroy (hb_subset_plan_t *plan);
184
185#endif /* HB_SUBSET_PLAN_HH */
186